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/***************************************************************************
* Copyright (c) 2017 Lorenz Lechner *
* *
* This file is part of the FreeCAD CAx development system. *
* *
* This library is free software; you can redistribute it and/or *
* modify it under the terms of the GNU Library General Public *
* License as published by the Free Software Foundation; either *
* version 2 of the License, or (at your option) any later version. *
* *
* This library is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU Library General Public License for more details. *
* *
* You should have received a copy of the GNU Library General Public *
* License along with this library; see the file COPYING.LIB. If not, *
* write to the Free Software Foundation, Inc., 59 Temple Place, *
* Suite 330, Boston, MA 02111-1307, USA *
* *
***************************************************************************/
#include <map>
#include <set>
#include <vector>
#include <BRep_Tool.hxx>
#include <Geom_BSplineSurface.hxx>
#include <Geom_Surface.hxx>
#include <Poly_Triangulation.hxx>
#include <Standard_Version.hxx>
#include <TColStd_Array1OfReal.hxx>
#include <TopLoc_Location.hxx>
#include "MeshFlattening.h"
#include "MeshFlatteningLscmRelax.h"
std::vector<ColMat<double, 3>> getBoundaries(ColMat<double, 3> vertices, ColMat<long, 3> tris)
{
// get a hashtable for all edges
// e: v1, v2, num
std::map<std::set<long>, std::vector<long>> hash_map;
std::vector<std::set<long>> hash_list;
std::map<long, std::vector<long>> neighbour_map;
std::vector<long> edge_vector_0;
std::vector<std::vector<long>> edge_vector;
for (long i = 0; i < tris.rows(); i++) {
for (long j = 0; j < 3; j++) {
long k = j + 1;
if (k == 3) {
k = 0;
}
long v1 = tris(i, j);
long v2 = tris(i, k);
std::set<long> hash {v1, v2};
hash_list.push_back(hash);
if (v1 < v2) {
hash_map[hash] = std::vector<long> {v1, v2, 0};
}
else {
hash_map[hash] = std::vector<long> {v2, v1, 0};
}
}
}
for (auto& hash : hash_list) {
hash_map[hash][2] += 1;
}
for (auto& hash : hash_map) {
if (hash.second[2] == 1) {
long v0 = hash.second[0];
long v1 = hash.second[1];
neighbour_map[v0].push_back(v1);
neighbour_map[v1].push_back(v0);
}
}
while (neighbour_map.size() != 0) {
long start_index = neighbour_map.begin()->first;
long close_index = start_index;
long next_index = neighbour_map[start_index][1];
long temporary_next;
edge_vector_0.clear();
edge_vector_0.push_back(close_index);
edge_vector_0.push_back(start_index);
neighbour_map.erase(start_index);
edge_vector_0.push_back(next_index);
while (next_index != close_index) {
temporary_next = neighbour_map[next_index][0];
if (temporary_next != start_index) {
start_index = next_index;
next_index = temporary_next;
}
else {
start_index = next_index;
next_index = neighbour_map[start_index][1];
}
neighbour_map.erase(start_index);
edge_vector_0.push_back(next_index);
}
edge_vector.push_back(edge_vector_0);
}
std::vector<ColMat<double, 3>> edges;
for (auto& edge : edge_vector) {
ColMat<double, 3> edge_vertices;
edge_vertices.resize(edge.size(), 3);
int i = 0;
for (auto index : edge) {
edge_vertices.row(i) = vertices.row(index);
i++;
}
edges.push_back(edge_vertices);
}
return edges;
}
FaceUnwrapper::FaceUnwrapper(const TopoDS_Face& face)
{
long i = 0;
// transform to nurbs:
TopLoc_Location location;
// triangulate:
const Handle(Poly_Triangulation) & triangulation = BRep_Tool::Triangulation(face, location);
if (triangulation.IsNull()) {
throw std::runtime_error("Null triangulation in face construction");
}
Standard_Integer numNodes = triangulation->NbNodes();
Standard_Integer numTriangles = triangulation->NbTriangles();
// compute uv coordinates
if (triangulation->HasUVNodes()) {
this->uv_nodes.resize(numNodes, 2);
i = 0;
for (Standard_Integer index = 1; index <= numNodes; ++index) {
const gp_Pnt2d& _uv_node = triangulation->UVNode(index);
this->uv_nodes.row(i) << _uv_node.X(), _uv_node.Y();
i++;
}
}
//
this->xyz_nodes.resize(numNodes, 3);
i = 0;
for (Standard_Integer index = 1; index <= numNodes; ++index) {
gp_Pnt _node = triangulation->Node(index);
this->xyz_nodes.row(i) << _node.X(), _node.Y(), _node.Z();
i++;
}
this->tris.resize(numTriangles, 3);
i = 0;
for (Standard_Integer index = 1; index <= numTriangles; ++index) {
int n1, n2, n3;
const Poly_Triangle& _tri = triangulation->Triangle(index);
_tri.Get(n1, n2, n3);
this->tris.row(i) << n1 - 1, n2 - 1, n3 - 1;
i++;
}
}
void FaceUnwrapper::findFlatNodes(int steps, double val)
{
std::vector<long> fixed_pins; // TODO: INPUT
lscmrelax::LscmRelax mesh_flattener(this->xyz_nodes.transpose(), this->tris.transpose(), fixed_pins);
mesh_flattener.lscm();
for (int j = 0; j < steps; j++) {
mesh_flattener.relax(val);
}
this->ze_nodes = mesh_flattener.flat_vertices.transpose();
}
ColMat<double, 3> FaceUnwrapper::interpolateFlatFace(const TopoDS_Face& face)
{
if (this->uv_nodes.size() == 0) {
throw(std::runtime_error(
"no uv-coordinates found, interpolating with nurbs is only "
"possible if the flattener was constructed with a nurbs."
));
}
// extract xyz poles, knots, weights, degree
const Handle(Geom_Surface) & _surface = BRep_Tool::Surface(face);
const Handle(Geom_BSplineSurface) & _bspline = Handle(Geom_BSplineSurface)::DownCast(_surface);
const TColStd_Array1OfReal& _uknots = _bspline->UKnotSequence();
const TColStd_Array1OfReal& _vknots = _bspline->VKnotSequence();
Eigen::VectorXd weights;
weights.resize(
static_cast<Eigen::Index>(_bspline->NbUPoles())
* static_cast<Eigen::Index>(_bspline->NbVPoles())
);
long i = 0;
for (long u = 1; u <= _bspline->NbUPoles(); u++) {
for (long v = 1; v <= _bspline->NbVPoles(); v++) {
weights[i] = _bspline->Weight(u, v);
i++;
}
}
Eigen::VectorXd u_knots;
Eigen::VectorXd v_knots;
u_knots.resize(_uknots.Length());
v_knots.resize(_vknots.Length());
for (long u = 1; u <= _uknots.Length(); u++) {
u_knots[u - 1] = _uknots.Value(u);
}
for (long v = 1; v <= _vknots.Length(); v++) {
v_knots[v - 1] = _vknots.Value(v);
}
nu = nurbs::NurbsBase2D(u_knots, v_knots, weights, _bspline->UDegree(), _bspline->VDegree());
A = nu.getInfluenceMatrix(this->uv_nodes);
Eigen::LeastSquaresConjugateGradient<spMat> solver;
solver.compute(A);
ColMat<double, 2> ze_poles;
ColMat<double, 3> flat_poles;
ze_poles.resize(weights.rows(), 2);
flat_poles.resize(weights.rows(), 3);
flat_poles.setZero();
ze_poles = solver.solve(ze_nodes);
flat_poles.col(0) << ze_poles.col(0);
flat_poles.col(1) << ze_poles.col(1);
return flat_poles;
}
FaceUnwrapper::FaceUnwrapper(ColMat<double, int(3)> xyz_nodes, ColMat<long int, int(3)> tris)
{
this->tris = tris;
this->xyz_nodes = xyz_nodes;
}
std::vector<ColMat<double, 3>> FaceUnwrapper::getFlatBoundaryNodes()
{
if (this->ze_nodes.size() == 0) {
throw(std::runtime_error("Flat vertices not yet computed"));
}
ColMat<double, 3> flat_vertices;
flat_vertices.resize(this->ze_nodes.rows(), 3);
flat_vertices.setZero();
flat_vertices.col(0) << this->ze_nodes.col(0);
flat_vertices.col(1) << this->ze_nodes.col(1);
return getBoundaries(flat_vertices, this->tris);
}
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